The present invention relates generally to water coolers and more particularly to a bottled water cooler having a sealed water delivery system in which the water bottle is vented to atmosphere through a filter only during water dispensing.
Most conventional bottled water coolers are unsealed systems in which the airspace within the bottle or within an associated water delivery chamber is open to atmosphere at all times. The need to provide a vent to atmosphere arises from the fact that drawing water from a fully sealed bottle creates a vacuum within the bottle which can prevent the water from being dispensed from the bottle. Many systems provide some means for maintaining the airspace above the water in the bottle in constant communication with the atmosphere, in order to relieve the vacuum crated as water is dispensed. Some systems dispense water from the bottle into a secondary reservoir which itself is open to atmosphere.
Although man open-to-atmosphere bottled water delivery systems are in use today, the re is growing interest in providing a vent on demand delivery system in which the bottled water is held in a normally sealed state impervious to the atmosphere and which is vented to atmosphere to relive vacuum pressures only during actual water dispensing. None of the solutions heretofore proposed for providing a vent on demand system having proven to be practical.
The present invention provides a practical solution to the need for a vent on demand water delivery system in a bottled water cooler. The invention employs a unique suction wand which seals at the mouth of the bottle and which includes a water suction tube, for drawing water from the bottom of the bottle, a vent tube for relieving vacuum pressures developed as water is withdrawn from the bottle and a water level sensing system which responds to water level by sensing its effect upon pressurized air trapped within a bell-shaped bulb well disposed at the lowermost end of the wand.
The vent tube and water delivery tube are substantially simultaneously coupled to atmosphere and to the dispensing faucet upon actuation of a single push button by the user. This same push button action closes an electrical switch momentarily after the vent and water delivery valves are opened which energizes a pump for drawing water from the bottle and delivering it to the dispensing height.
The vent on demand system is well adapted for use in applications which provide both heated and chilled water as well as optional room temperature cooking water through a single dispensing faucet. The vent valve and both hot and cold water dispensing valves are positioned adjacent one another on a valve mounting plate with push button actuators situated so that actuation of the hot water button actuates the vent and hot water delivery valves while actuation of the cold water button actuates the vent and cold water delivery valves. In this fashion, a single vent valve may be shared by both hot and cold water delivery systems.
By sensing trapped air under pressure within the bulb well disposed at the lowermost portion of the bottle, a pressure switch is operated to de-energize the pump before the bottle runs dry. This prevents unwanted air from entering the water dispensing plumbing system. A check valve is provided in the wand to prevent air from entering the system when the wand is withdrawn from a bottle during bottle replacement.
For a more complete understanding of the invention, it objects and advantages, reference may be had to the following specification and to the accompanying drawings.